In a multimedia service, video stream transmission has not only a high requirement for network bandwidth but also has low tolerance for delay, jitter, and packet loss, which, accordingly, imposes a unique requirement on a network device used for video stream transmission. At present, a media stream delivery quality index, such as Media Delivery Index (MDI) defined in the Request for Comments (RFC) 4445 standard may be used to measure a user's expected quality of experience of a video at a network level, in order to effectively evaluate a multimedia service support capability of a network device. The quality of experience (QoE) is a subjective feeling of an end user on service performance provided by a mobile network. The QoE can indicate experience and feeling of an end user on a service and a network by using an approximate quantification method, and reflect a gap between the current service and network quality and the user's expectation.
The MDI is not affected by a video coding scheme and is a simple and extensible measurement scheme. However, the MDI is more suitable for an application scenario in which the User Datagram Protocol (UDP) is used as a transmission protocol. At present, the most widely used HyperText Transfer Protocol (HTTP) video is based on the Transmission Control Protocol (TCP), and the MDI cannot be well applied in an application scenario in which the TCP is used as a transmission protocol. The reason is that the MDI includes two parameters, namely, delay factor (DF) and media loss rate (MLR). A calculation of the DF in the MDI converts a network jitter to a requirement for media stream decoding buffering but a converted result cannot directly reflect a variation of the subjective experience. The MLR is not significant for the evaluation of the subjective experience. Therefore, the QoE of an HTTP video cannot be directly acquired by using the MDI measurement scheme.